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This page is alzhub.org's plain-English summary of a published study, not the paper itself. It is generated from the record we hold for this study, sourced and linked below — check the original for the full text and methods.

✓ Peer-reviewed alzhub usefulness score 58 out of 100. Genetics

Topic: Brain proteins, microglia and lab models

Objective To characterize and compare measurements of the posterior cingulate glucose metabolism, the hippocampal glucose metabolism, and hippocampal volume so as to distinguish cognitively normal, late-middle-aged persons with 2, 1, or 0 copies of the apolipoprotein E (APOE) ε4 allele, reflecting 3 levels of risk for late-onset Alzheimer disease. Design Cross-sectional comparison of measurements of cerebral glucose metabolism using 18F-fluorodeoxyglucose positron emission tomography and measurements of brain volume using magnetic resonance imaging in cognitively normal ε4 homozygotes, ε4 heterozygotes, and noncarriers. Setting Academic medical center. Participants A total of 31 ε4 homozygotes, 42 ε4 heterozygotes, and 76 noncarriers, 49 to 67 years old, matched for sex, age, and educational level. Main outcome measures The measurements of posterior cingulate and hippocampal glucose metabolism were characterized using automated region-of-interest algorithms and normalized for whole-brain measurements. The hippocampal volume measurements were characterized using a semiautomated algorithm and normalized for total intracranial volume. Results Although there were no significant differences among the 3 groups of participants in their clinical ratings, neuropsychological test scores, hippocampal volumes (P = .60), or hippocampal glucose metabolism measurements (P = .12), there were significant group differences in their posterior cingulate glucose metabolism measurements (P = .001). The APOE ε4 gene dose was significantly associated with posterior cingulate glucose metabolism (r = 0.29, P = .0003), and this association was significantly greater than those with hippocampal volume or hippocampal glucose metabolism (P Conclusions Although our findings may depend in part on the analysis algorithms used, they suggest that a reduction in posterior cingulate glucose metabolism precedes a reduction in hippocampal volume or metabolism in cognitively normal persons at increased genetic risk for Alzheimer disease.

Cite this study APA, Vancouver, BibTeX · download .bib or .ris

APA 7th

Protas, H. D., Chen, K., Langbaum, J. B., Fleisher, A. S., Alexander, G. E., Lee, W., et al. (2013). Posterior cingulate glucose metabolism, hippocampal glucose metabolism, and hippocampal volume in cognitively normal, late-middle-aged persons at 3 levels of genetic risk for Alzheimer disease. JAMA neurology. https://doi.org/10.1001/2013.jamaneurol.286

Vancouver

Protas HD, Chen K, Langbaum JB, Fleisher AS, Alexander GE, Lee W, et al. Posterior cingulate glucose metabolism, hippocampal glucose metabolism, and hippocampal volume in cognitively normal, late-middle-aged persons at 3 levels of genetic risk for Alzheimer disease. JAMA neurology. 2013. doi:10.1001/2013.jamaneurol.286. PMID: 23599929.

BibTeX

@article{protas2013-23599929,
  author  = {Protas, H. D. and Chen, K. and Langbaum, J. B. and Fleisher, A. S. and Alexander, G. E. and Lee, W. and Bandy, D. and de Leon, M. J. and others},
  title   = {{Posterior cingulate glucose metabolism, hippocampal glucose metabolism, and hippocampal volume in cognitively normal, late-middle-aged persons at 3 levels of genetic risk for Alzheimer disease}},
  journal = {JAMA neurology},
  year    = {2013},
  doi     = {10.1001/2013.jamaneurol.286},
  pmid    = {23599929},
  url     = {https://doi.org/10.1001/2013.jamaneurol.286}
}

Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.

Key findings

Why it matters

In cognitively normal late-middle-aged adults, APOE epsilon4 gene dose was associated with lower posterior cingulate glucose metabolism, while hippocampal volume and hippocampal glucose metabolism did not differ significantly among groups. This is an observational imaging finding and does not test treatment or prevention.

Study details

How this study scored 58/100
How this study's score is builtJournal tier 9 of 10; Journal's citation record 2 of 4; Study design 4 of 12; Strength of evidence 1 of 5; Peer-review validation 10 of 10; How recent 1 of 5; Sample size 1 of 4; Effect reported 0 of 3; Studied in people 3 of 3; Randomized / blinded 0 of 2; Times cited 5 of 7; Citations per year 3 of 5; Impact for its field and year 4 of 6; Cited by studies here 3 of 6; Still being cited 2 of 4; Senior author's track record 4 of 4; Institution's track record 2 of 3; Multicenter collaboration 2 of 3; Indexed in PubMed 2 of 2; Free to read 0 of 2. Total 58 of 100.58 of 100 points earned42 not earned

Published in a leading specialty journal, and it is a snapshot of people at one point in time. Scored zero for effect reported and randomized / blinded because the record does not state it.

ComponentPointsWhy
Journal tier 9 / 10 Tier 2 — leading specialty journal (JAMA neurology)
Journal's citation record 2 / 4 JAMA Neurology: journal h-index 235 (OpenAlex, 2026-10-29)
Study design 4 / 12 A snapshot of people at one point in time
Strength of evidence 1 / 5 Rated “low” in our summary
Peer-review validation 10 / 10 Peer-reviewed. Published as an article in a named peer-reviewed journal.
How recent 1 / 5 2013 — within 20 year(s) of the newest study here
Sample size 1 / 4 31 participants
Effect reported 0 / 3 No effect size reported — scores zero (not stated in the record — scored 0)
Studied in people 3 / 3 Studied in people (participant count stated)
Randomized / blinded 0 / 2 No randomization or blinding stated — scores zero (not stated in the record — scored 0)
Times cited 5 / 7 Cited 158 times (OpenAlex, 2026-10-10)
Citations per year 3 / 5 10.5 citations a year over 15 year(s) since 2013
Impact for its field and year 4 / 6 Cited 8.0× the average for papers of its field and year (OpenAlex FWCI)
Cited by studies here 3 / 6 Cited by 10 other studies in this library
Still being cited 2 / 4 Cited 33 times in 2024–2026 (2026 still in progress; OpenAlex)
Senior author's track record 4 / 4 Last-listed author Eric M. Reiman: h-index 151 (OpenAlex, whole career)
Institution's track record 2 / 3 University of California, San Francisco: institution h-index 1,915 (OpenAlex)
Multicenter collaboration 2 / 3 OpenAlex lists 9 institution(s) in 1 country
Indexed in PubMed 2 / 2 Indexed in PubMed (PMID 23599929)
Free to read 0 / 2 Behind a paywall — scores zero
Total 58 / 100 —

What each of these 20 components measures, and what this score is not →

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